Functional requirements of the liver isoform of phosphofructokinase-1 in breast cancer cell migration

Increased aerobic glycolysis and increased cell motility are hallmarks of metastatic cancer. Migrating cancer cells are highly polarized, suggesting that glycolytic enzymes could be spatially regulated. Here, we investigated the role of the liver isoform of the 'gatekeeper' glycolytic enzyme phosphofructokinase-1 (PFKL) in breast cancer cell migration. Depletion of PFKL significantly decreased migration velocity and directional sensing. We have observed the localization of PFKL to lamellipodia of migrating breast cancer cells, where it colocalized with hexokinase-2 and pyruvate kinase M2. We then investigated the functional requirements of PFKL for directional migration. First, we found that expression of catalytically inactive PFKL or indirect pharmacological inhibition of PFKL activity significantly decreased directional migration. Second, we discovered that disrupting PFKL filament formation by expression of a filament-incompetent mutant decreased PFKL recruitment to lamellipodia and directional sensing, without altering migration velocity. These findings indicate that both catalytic activity and subcellular localization are required for directional migration in breast cancer cells. These results suggest a novel function of PFKL filaments in cells and provide insight into the function of compartmentalized glycolysis in the cytoplasm.